After first calling it "collateral damage," then then saying that Afghan forces needed support against the resurgent Taliban, the US has admitted it ordered a deadly air-attack on a hospital in Afghanistan -- but calls it a mistake, not a war crime. Doctors Without Borders, which ran the hospital, has demanded an international investigation. The incident has dramatized the resurgence of the Taliban, potentially upsetting US plans to withdraw almost completely by the end of next year. The City of Kunduz, where the attack occurred, is now a shambles, and tens of thousands of Afghans are desperate to leave their country. Do setbacks and blunders make the case for being stronger and staying longer?